ClearNote Health

The lab that reads cancer's footnotes

Somewhere in San Diego's Science Center Drive, a vial of ordinary blood is doing something quietly subversive. It is being asked a question oncology usually saves for too late in the story: is anything starting to go wrong, right now, while it can still be stopped? ClearNote Health was built to answer that question - not with a scan, not with a needle in the pancreas, but with the chemical marks cancer leaves on DNA long before a tumor announces itself.

The company is a molecular diagnostics outfit of roughly 55 people. Its flagship product, the Avantect Pancreatic Cancer Test, looks for a cancer that is notorious for being found late and treated worse. Its toolkit is an epigenomic platform built on 5-hydroxymethylcytosine - 5hmC for short - paired with cell-free DNA analysis and a stack of machine learning. The pitch is almost annoyingly simple: catch the deadliest cancers early, from a standard blood draw, when treatment still has the upper hand.

Late is the whole problem

Pancreatic cancer is a scheduling problem disguised as a biology problem. By the time it produces symptoms, the calendar has usually already decided the outcome. Survival depends, brutally and predictably, on when you find it - and for most patients that is far too late. Ovarian cancer, the company's second target, runs the same cruel playbook: quiet, then sudden, then advanced.

The conventional answer has been to look harder with imaging or to wait for symptoms - which is a bit like installing a smoke detector that only sounds once the house is fully involved. ClearNote's contrarian read was that the earliest evidence isn't a lump you can see. It's a pattern of chemical modifications on DNA shed into the bloodstream, the molecular equivalent of a margin note. Read the notes, and you might read the disease before it can be felt.

A Stanford lab, a stubborn molecule

The company began life in 2016 as Bluestar Genomics, spun out of the Stanford laboratory of Stephen Quake - a physicist-turned-bioengineer whose name keeps appearing wherever single-molecule measurement and cell-free DNA collide. The founding bet was that 5hmC, an epigenetic mark most cancer tests politely ignored, carried real signal about which cells were quietly going wrong.

It was, for a while, an unfashionable position. Most of the field chased mutations and methylation. 5hmC was the overlooked middle child of the epigenome. In 2022 the company changed its name to ClearNote Health - same science, sharper mission - and pointed the platform squarely at the cancers where early detection changes the most lives. Today it is led by CEO Dave Mullarkey, with Samuel Levy as Chief Scientific Officer.

What a blood draw can be taught to say

The Avantect Pancreatic Cancer Test is aimed at people who actually carry elevated risk: those age 50 or older newly diagnosed with type 2 diabetes, people with a family history, and those with known genetic predisposition. That focus matters. A test is only as useful as the population you point it at, and ClearNote points carefully.

The enhanced version, launched in 2026, is what the company calls multiomic - it stacks 5hmC epigenomic patterns on top of genomic and genotyping data from cell-free DNA, adds a glycan biomarker, and lets optimized machine learning weigh the evidence. Around the flagship sits a small family: an Avantect Ovarian Cancer Test, a broader Multi-Cancer Detection Test, and an epigenomics platform offered to biopharma partners for drug development. One technology, several front doors.

Numbers, and the people who checked them

Diagnostics live or die by validation, and ClearNote has collected the unglamorous stamps that matter: an FDA Breakthrough Device Designation in 2021, CAP accreditation for its lab in 2022, New York State Department of Health approval in early 2025, and its first in vitro diagnostic approval via UKCA marking later that year. Reimbursement followed - CPT codes and CMS payment determinations - because a test no one pays for is a science project, not a product.

The validation that turns heads, though, came from the National Cancer Institute, which selected ClearNote's Avantect Multi-Cancer Detection Test as one of just two non-invasive blood-based technologies for its Vanguard study. When a federal cancer institute puts your assay through its paces, the skeptics at least have to lower their eyebrows.

Then there's the money, which has its own way of validating. The $70M Series C in 2021 funded the science; the $52M Series D in May 2026 - led by Mattias Westman, alongside a strengthened leadership bench - is meant to scale it from one disease into many. Investors don't tend to fund a second act unless the first one held up.

Early, on purpose

Strip away the assay chemistry and the company has one organizing idea: extend and improve the lives of people at risk for high-mortality cancers by finding the disease early. Not screening everyone for everything - that way lies false alarms and exhausted clinicians - but pointing a precise tool at the people most likely to benefit, and giving their doctors a head start measured in stages, not symptoms.

The same vial, a different ending

ClearNote is not alone in the liquid biopsy race - GRAIL, Exact Sciences, Guardant, Freenome and Delfi are all chasing versions of the same future. What separates ClearNote is the bet it placed early and never abandoned: that 5hmC, the overlooked mark, would turn out to carry the signal everyone else stepped over. A decade in, the regulators, the reimbursers and the National Cancer Institute have all, in their own bureaucratic dialects, agreed it was worth a look.

So return to that vial of blood on Science Center Drive. A few years ago, the honest answer to "is anything starting to go wrong?" was a shrug and a wait. ClearNote Health's wager is that the shrug is optional - that the deadliest cancers leave notes, that the notes can be read, and that reading them in time is the difference between a screening and a save. The vial hasn't changed. What it can now say has.